Semiconductor structures of anti-fuse devices and core devices with different dielectric layers and preparation method thereof

A preparation method of the semiconductor structure includes: providing a substrate including a core device region and an anti-fuse device region; forming a first dielectric layer covering the core device region and the anti-fuse device region; forming a second dielectric layer covering the first dielectric layer and having a dielectric constant larger than a dielectric constant of the first dielectric layer; removing the second dielectric layer on the anti-fuse device region; and forming a conductive layer covering the first dielectric layer on the anti-fuse device region and the second dielectric layer on the core device region.